Lg Ally Screen Wont Turn OnSupport

Okay My Lg Ally Is On I Can Turn It Off & On & When I Get Texts And Calls I Hear It Vibrate I Can Answer A Call But Idk Whos Calling Because My Screen Is Black But Obviously My Phone Works Its On Velocity v1.2 , Please Help

Okay My Lg Ally Is On I Can Turn It Off & On & When I Get Texts And Calls I Hear It Vibrate I Can Answer A Call But Idk Whos Calling Because My Screen Is Black But Obviously My Phone Works Its On Velocity v1.2 , Please Help